The present invention relates to electromagnetic audio transducers and particularly to an improved flat or planar transducer of relatively high efficiency and broad frequency response.
A variety of transducer or loudspeaker designs are used for providing sound systems having broad frequency responses and high output volumes. A number of the most popular transducers are relatively large and in particular have significant measurements in three dimensions. These speakers, for example, often utilize conical or other three dimensional vibrating members which occupy a significant volume and which require a correspondingly large mounting space.
It has been proposed to use transducers having a flat or planar form whereby a significant reduction can be made in the space required and so that the transducers are essentially a two dimensional device.
Difficulties have been encountered in prior planar transducers where one or all of the following deficiencies are present. One problem encountered with planar transducers is a limitation in their frequency range with reduced frequency responses being obtained at both the high and low ends. Certain planar speaker designs also have been found to be critical as regards the element spacing and the allowable spacing tolerances of the magnets and the diaphragms. The problem of controlling tolerances is present both during the transducer assembly and during transducer use and adjustment or repair. Additionally, deficiencies have been encountered in obtaining a sufficiently strong power output.
The improved planar transducer of the present invention has a design which permits a rapid and relatively simple assembly where the necessary element spacings and tolerances are automatically obtained as a result of the transducer design. Additionally, the planar transducer of the present invention provides a broad and uniform frequency response with an adequate power output.
These improvements are obtained by utilizing a preferred arrangement of magnet supporting iron backing members in combination with non-magnetic spacing and diaphragm framing members fitted together in a solid multilayer stack with the optimum magnet and membrane spacings resulting automatically from this arrangement of the elements.
Accordingly, an object of the present invention is to provide an improved planar audio transducer.
Another object of the present invention is to provide an improved planar transducer with a broad and uniform frequency response.
Another object of the present invention is to provide an improved planar acoustic transducer in which the necessary element spacings are easily obtained during assembly and are maintained thereafter during use and possible repair or adjustment.
Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.